https://doi.org/10.1140/epja/i2019-12715-5
Regular Article - Theoretical Physics
Magnetic dipole moment in relativistic quantum mechanics
Department of Physics, The University of Arizona, 85721, Tucson, AZ, USA
* e-mail: rafelski@physics.arizona.edu
Received:
4
December
2018
Accepted:
1
February
2019
Published online:
26
March
2019
We investigate relativistic quantum mechanics (RQM) for particles with arbitrary magnetic moment. We compare two well known RQM models: a) Dirac equation supplemented with an incremental Pauli term (DP); b) Klein-Gordon equations with full Pauli EM dipole moment term (KGP). We compare exact solutions to the external field cases in the limit of weak and strong (critical) fields for: i) homogeneous magnetic field, and ii) the Coulomb 
-potential. For i) we consider the Landau energies and the Landau states as a function of the gyromagnetic factor (g-factor). For ii) we investigate contribution to the Lamb shift and the fine structure splitting. For both we address the limit of strong binding and show that these two formulations grossly disagree. We discuss possible experiments capable of distinguishing between KGP and DP models in laboratory. We describe the impact of our considerations in the astrophysical context (magnetars). We introduce novel RQM models of magnetic moments which can be further explored.
© Società Italiana di Fisica / Springer-Verlag GmbH Germany, part of Springer Nature, 2019
